Wivenhoe Dam Improvement Project

Wivenhoe Dam is one of several dams to be upgraded as part of Seqwater's Dam Improvement Program. Wivenhoe Dam is the main drinking water source for South East Queensland, in addition to providing flood mitigation benefits. The dam plays an important role in the SEQ Water Grid, and its continued performance and safety is critical to the region.

The dam improvement project will ensure the dam continues to operate safely in extreme weather events and provides water security for years to come.

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About the project

Planning is underway on the Wivenhoe Dam Improvement Project, with the project currently in Options Analysis phase.

As Somerset and Wivenhoe Dams operate as one system for both water supply and flood mitigation, the outcomes of the Somerset Dam Improvement Project will inform considerations for Wivenhoe Dam. A detailed business case for the Somerset Dam Improvement Project is being prepared.

Major dam upgrades are extremely complex and take years to plan to ensure the best design and constructability option is determined to meet the project objectives and value for money.

We are committed to keeping the community informed and will provide further information as planning progresses.

Reduced full supply level

While planning is underway, Wivenhoe Dam will continue operating at a reduced full supply level of 90%.

Lowering water levels is an industry-accepted practice to manage dam safety and demonstrates our commitment to the ongoing safety of dam infrastructure. South East Queensland has a safe, reliable, and resilient water supply system, stemming from careful and ongoing water security planning and a diverse asset base which allows Seqwater to supplement supply in a timely way when needed.

The reduced level does not significantly impact the long-term water supply security for the region. Periodic reviews will continue until the dam is upgraded to ensure dam safety, water supply and long-term water security are appropriately managed.

Find out more

Contact the team

Email [email protected]
Online feedback form
Phone 3432 7000 (Monday to Friday, 9am to 5pm)

News and updates
FAQs

Geotechnical investigations underway at Wivenhoe Dam

26 Jun 2024

Geotechnical investigations are underway at Wivenhoe Dam.

The specialist work is being undertaken by engineering company GHD.

These investigations will carefully assess the ground conditions and help to further understand the dam’s foundations. The work is supporting up to 10 jobs on site. These investigations will continue until late 2024, weather and site conditions permitting.

More information is available in this Ministerial Media Statement.

Geotechnical investigations underway

24 Jun 2024

As part of the Options Analysis phase, geotechnical investigations will be conducted to better understand the ground conditions (soil and rock).

The geotechnical investigations are expected to progressively occur around Wivenhoe Dam from June to late 2024, between 6.30am and 6.30pm on weekdays, weather and ground conditions permitting. Some weekend work may be required.

Residents and visitors can expect to see an increased number of workers around the lake and local area, as well as:

Traffic control: residents may experience short-term traffic disruptions. Please follow the directions of traffic controllers and signage onsite.
Minor noise, possible dust and vibration may be experienced.
Access: visitors to park locations may be limited at times for public safety.

Why does Wivenhoe Dam need to be upgraded?

Wivenhoe Dam is one of several dams to be upgraded as part of Seqwater’s Dam Improvement Program. Like all major infrastructure, dams are regularly assessed and upgraded to comply with improvements to engineering standards and guidelines. Seqwater is required to comply with the Queensland Dam Safety Guidelines under the Water Supply (Safety and Reliability) Act 2008.

Wivenhoe Dam was built between 1977 and 1984 and with an auxiliary spillway constructed in 2005. Since then, there have been significant changes including:

population growth downstream
advances in dam design
improved estimation of extreme rainfall and flood events
improved understanding of earthquake probabilities and loads.

How long will the Wivenhoe Dam Improvement Project take?

As Somerset and Wivenhoe Dams operate as one system for both water supply and flood mitigation, the outcomes of the upstream Somerset Dam Improvement Project will inform planning considerations for the downstream Wivenhoe Dam Improvement Project.

The Wivenhoe Dam Improvement Project is currently in the Options Analysis planning phase. Once this is completed, a Detailed Business Case will be prepared. As Somerset and Wivenhoe Dams operate as one system for both water supply and flood mitigation, the outcomes of the Somerset Dam Improvement Project will inform final considerations for Wivenhoe.

Seqwater recognises that these projects have had a long planning phase. Major dam upgrades have complex design and approval requirements and can take years to plan, and it is prudent that Seqwater takes the time to get it right to ensure the best option is selected to meet project objectives, regulatory requirements and deliver value for money.

What will the upgrade look like?

The Options Analysis for Wivenhoe Dam Improvement Project is underway and Seqwater is considering a number of options which will achieve the objectives required of the dam improvement project to meet regulatory requirements.

Will the Wivenhoe Dam Improvement Project impact the Brisbane Valley Highway?

The Brisbane Valley Highway is located on the Wivenhoe dam crest, and the highway will be required to remain in service during the construction of the dam upgrade. Planning is underway on an Options Analysis to determine how this will be achieved. The Department of Transport and Main Roads (TMR) owns and operates this major highway, and Seqwater is engaging with TMR to discuss the status of the Wivenhoe Dam Improvement Project, potential impacts, and mitigations. Further information will be available as the Wivenhoe Dam Improvement Project progresses.